Teaching content, the first lesson of the first volume of mathematics in the third grade of primary school, "Preliminary Understanding of Fractions". It is students' initial understanding of the meaning of fractions on the basis of mastering some integer knowledge. It is the expansion of the concept from integer to fraction and a leap in students' cognition. Fractions and integers are quite different in meaning and reading and writing methods. It will be difficult for students to learn scores for the first time. Therefore, in teaching, I create familiar and interesting realistic situations for students. Through self-study, cooperative inquiry, hands-on operation, group communication and practical demonstration, students can actively build mathematical knowledge, understand the specific meaning of a score and help them establish the initial concept of a score.

Teaching objectives

1. Students can initially know the score of the score through autonomous learning and can read and write the score correctly.

2. Through group cooperative exploration, hands-on operation, observation, imagination, folding, painting and other activities, let students experience the generation of scores, help students intuitively perceive the formation process of a score, and develop their initial logical ability.

3. Through various learning activities, let students feel the connection between mathematics and life, and cultivate students' spirit of exploration and independent learning. Be able to use what you have learned to solve practical problems in life.

Teaching emphases and difficulties:

Know a little.

Teaching preparation

Students prepare various shapes of paper and watercolor pens.

First, create situations and introduce topics.

1, listen to the music "Full Moon on August 15th"

Teacher: After listening to this song just now, what festival did you think of? Mid-Autumn Festival is a traditional festival in China. What should everyone eat? Have you ever shared moon cakes with your relatives or friends? Now the teacher wants everyone to share another piece of moon cake.

Step 2 feel the average score

Teacher: Teacher, here are four moon cakes, which should be distributed to two children equally. How much should everyone get? (The teacher draws four circles instead of moon cakes on the blackboard, names the front edge and writes: "To divide the points equally, the formula is 4 ÷ 2 = 2 (each). )

Teacher: The average score on the blackboard.

Teacher: Now there is only one moon cake, which is distributed to two children equally. How to divide it? (student: half)

Think about it: four moon cakes are distributed to two people equally, and each person gets two, so it can be represented by a "2". Can this "half" be expressed by such a number? What number shall we use instead? This is what we are going to learn today.

Second, autonomous learning.

(1) Learn by yourself what "half" is and what it means.

1, please open page 90 of the book for self-study.

2, teachers show self-study requirements:

Want to know what number "half" can represent?

Want to know how to write and pronounce "this number"?

You know, "this number" is made up of several parts. What are their names?

Want to know what "this number" means?

Let the students read the questions together first, and then study independently. )

3. If students have difficulties in autonomous learning, they can work in groups to solve the above problems.

4, the group elected representatives to report the self-study, after the report is completed, please other group representatives to evaluate, require complete expression.

5. Teacher: Answer the blackboard with the students.

(2) Do it yourself and feel the "score".

Transition: Everyone knows that a moon cake is divided into two parts on average, one of which is 1/2. What if you divide the picture into chapters?

1, Teacher: Given two numbers, please ask two students to come forward and divide the numbers into four or three equally. How much is each number? Let the two students come forward and divide a little, fold a little, color one of them, and then tell their own operation process completely. )

2. Exhibition works: 1/4 1/3

3. Scores of students reading together: 1/2, 1/4, 1/3.

Teacher: Are they the only ones who get grades? (No, there are many) What scores can you name? ( 1/5 、 1/6 、 1/7、…)

Summary: Students, just now, everyone learned to divide an object into several parts, one of which is the score of this object, which is really good!

Third, cooperative inquiry and feedback exchange.

Transition: Students, now the teacher wants you to use the pieces of paper prepared by yourself, fold them according to the scores you said, color them and write down the scores, ok?

1, team work, start to discount, and see who created a different score from others.

2, the teacher patrol, appropriate to help students with difficulties.

3. Communicate in groups and tell each other what score you are folding and how to fold it. And tell the meaning of this score completely.

4. Show the work, show it by name, and tell the meaning of the soundtrack. Ask other groups to evaluate.

Fourth, practice feedback.

1. Students independently complete the first question on page 9 1 of the textbook.

2. Let students talk about their own ideas. Why are you doing this?

3. The teacher shows the true or false questions:

(1), judge whether the shaded part represented by the following score is correct. (Figure omitted)

(2) Extension problem: Lan Lan spent 10 yuan bought a book, and Xiao Ming spent 5 yuan to buy a book. Ask Xiao Ming if the money of Lan Lan Hua is 1/2. Please provide a justification for the answer.

Verb (abbreviation of verb) abstract

Students, what have you learned from this class?

Teaching design of intransitive verbs

A preliminary understanding of one-point score

Meaning: divide an object or figure into several parts, one of which is the score of the object or figure.

Like this: 1/2, 1/3, 1/4, 1/5, 1/6, 1/7, … are all fractions.